Randall Garrett

“ Dr. Smathers glanced up hopelessly at the other two men. “That eliminates the vitamins,” he said, sotto voce. He looked back at the patient. “No aspirin? No APC’s? You didn’t have a headache at all?”
MacNeil shook his head firmly. “I don’t get headaches much.” Again he essayed a feeble smile. “I ain’t like you guys, I don’t overwork my brains.”
“I’m sure you don’t,” said Smathers. Then his eyes gleamed. “You have quite a bit of stomach trouble, eh? Your digestion bad?”
“Yeah. You know; I told you about it. I get heartburn and acid stomach pretty often. And constipation.” ”

“ Colonel Fennister and Major Grodski sat at the table in the lab, munching on banana-pears, blissfully enjoying the sweet flavor and the feeling of fullness they were imparting to their stomachs.
“MacNeil can’t stay in the service, of course,” said Fennister. “That is, not in any space-going outfit. We’ll find an Earthside job for him, though. Maybe even give him a medal. You sure these things won’t hurt us?”
Dr. Pilar started to speak, but Petrelli cut him off.
“Positive,” said the chemist. “After we worked it out, it was pretty simple. The ‘poison’ was a chelating agent, that’s all. ”

“ Petrelli raised a thin eyebrow. “What’s the difference between a sign and a symptom?”
“A sign,” said Smathers testily, “is something that can be objectively checked by another person than the patient. Lesions, swellings, inflammations, erratic heartbeat, and so on. A symptom is a subjective feeling of the patient, like aches, pains, nausea, dizziness, or spots before the eyes.
“And MacNeil is beginning to get all kinds of symptoms. Trouble is, he’s got a record of hypochondria, and I can’t tell which of the symptoms are psychosomatic and which, if any, might be caused by the fruit.” ”

“ Smathers, now noticeably thinner in the face. The medic was looking over MacNeil’s record. “But if that fruit kills monkeys and rats and guinea pigs, how can a man eat it?”
“Animals differ,” said Smathers, without taking his eyes off the record sheets. He didn’t amplify the statement.
The colonel looked back at Pilar.
“That’s the trouble with test animals,” Dr. Pilar said, ruffling his gray beard with a fingertip. “You take a rat, for instance. A rat can live on a diet that would kill a monkey. If there’s no vitamin A in the diet, the monkey dies, but the rat makes his own vitamin A ”

“ Trouble was, no one had thought of being attacked by something immensely greater than a blue whale, especially since there was no animal larger than a small rhino on the whole planet. Who, after all, could have expected an attack by a blind, uncaring colossus—a monster that had already been dying before it made its attack? ”

“ Smathers, still peering. “There’s something different about him, that’s all.”
Petrelli forcibly restrained his temper. “Very funny,” he snapped.
“Not funny at all,” Smathers snapped back. “No two human beings are identical—you know that.” He lifted his gaze from the eyepiece of the instrument and settled in on the chemist. “He’s got AB blood type, for one thing, which none of the volunteers had. Is that what makes him immune to whatever poison is in those things? I don’t know.
“Were the other three allergic to some protein substance in the fruit, while MacNeil isn’t? I don’t know. ”

“ Just because a man can do something others can’t does not, unfortunately, mean he knows how to do it. One man could eat the native fruit and live ... but how?
“And that,” said Colonel Fennister glumly, “appears to be that.”
The pile of glowing coals that had been Storage Shed Number One was still sending up tongues of flame, but they were nothing compared with what they’d been half an hour before.
“The smoke smells good, anyway,” said Major Grodski, sniffing appreciatively. ”

“ Pilar cut him off. “It may come to fighting, colonel, but, even if perfect discipline is maintained, what I say will still be true. Some will die early, leaving more food for the remaining men. It has been a long time since anything like this has happened on Earth, but it is not unknown in the Space Service annals.”
The colonel pursed his lips and kept his silence. He knew that what the biologist said was true.
“The trouble is,” said Petrelli snappishly, “that we are starving in the midst of plenty. We are like men marooned in the middle of an ocean with no water ”

“ Carbon, hydrogen, and oxygen, plus varying proportions of phosphorus, potassium, iodine, nitrogen, sulfur, calcium, iron, magnesium, manganese, and strontium, plus a smattering of trace elements, seem to be able to cook up all kinds of life under the strangest imaginable conditions. ”

“ Pilar made it half a question.
“It’s possible,” agreed Smathers. “A hypochondriac will sometimes leave off dosing himself if there’s a doctor around to do it for him. As long as the subconscious need is filled, he’s happy.” But he was shaking his head.
“What’s the matter?” Pilar asked.
Smathers pointed at the bottles. “Some of those are mislabeled. They all say vitamins of one kind or another on the label, but the tablets inside aren’t all vitamins. MacNeil’s been giving himself all kinds of things.” ”

“ That’s why we ask for volunteers. But we haven’t lost a man so far. Sometimes a volunteer will get pretty sick, but if a food passes all the other tests, you can usually depend on its not killing a human being.”
“I gather that this is a pretty unusual case, then?”
Pilar frowned. “As far as I know, [73] yes. But if something kills all the test animals, we don’t ask for humans to try it out. We assume the worst and forget it.” ”

“ Do you know how much botulin toxin it takes to kill a man? A fraction of a milligram!”
Smathers looked as though he were about to quote the minimum dosage, so Petrelli charged on: “If you think anyone could isolate an unknown organic compound out of a—”
“Gentlemen! Please!” said Dr. Pilar sharply. “I realize that this is a strain, but bickering won’t help. What about your latest tests on MacNeil, Dr. Smathers?”
“As far as I can tell, he’s in fine health. And I can’t understand why,” said the physician in a restrained voice.
Pilar tapped one of the report sheets. “You mean the vitamins?” ”

“ They couldn’t do their job. The body had to quit making hemoglobin, because hemoglobin needs iron. So, since there was no hemoglobin in the bloodstream, the patient developed sudden pernicious anemia and died of oxygen starvation.”
Colonel Fennister looked suddenly at Dr. Smathers. “I thought you said the blood looked normal.”
“It did,” said the physician. “The colorimeter showed extra hemoglobin, in fact. But the chelating agent in the fruit turns red when it’s connected up with iron—in fact, it’s even redder than blood hemoglobin. ”

“ You saw the test run I did for you.”
The colonel nodded. He’d watched the little chemist add an iron salt to some of the fruit juice and seen it turn red. Then he’d seen it turn pale yellow when a magnesium salt was added. “But what’s a chelating agent?” he asked.
“There are certain organic compounds,” Dr. Petrelli explained, “that are ... well, to put it simply, they’re attracted by certain ions. Some are attracted by one ion, some by another. The chelating molecules cluster around the ion and take it out of circulation, so to speak; they neutralize it, in a way. ”

“ The fact that the atmospheric potential—the voltage and even the amperage difference between the low-hanging clouds and the ground below—was immensely greater than that of Earth, that had already been determined. But the compound and the defenses surrounding it had already been compensated for that factor. ”

“ After much thinking—if we may so refer to MacNeil’s painful cerebral processes—he decided to ask a few cautious questions.
Going without food tends to make for mental fogginess, snarling tempers, and general physical lassitude in any group of men. And, while [71] quarter rations were not quite starvation meals, they closely approached it. It was fortunate, therefore, that MacNeil decided to approach Dr. Pilar.
Dr. Petrelli’s temper, waspish by nature, had become positively virulent in the two weeks that had passed since the destruction of the major food cache. Dr. ”

“ And the molecules containing the sequestered iron tend to stick to the outside of the red blood cells, which threw the whole test off.”
“As I understand it, then,” said Major Grodski, “the antidote for the ... uh ... chelating agent is magnesium?”
“That’s right,” said Dr. Petrelli, nodding. “The stuff prefers magnesium ions to ferrous ions. They fit better within the chelating ring. Any source of magnesium will do, so long as there’s plenty of it. MacNeil was using milk of magnesia, which is the hydroxide, for ‘gastric acidity’. It’s changed to chloride in the stomach. ”

“ Smathers, over in G Section.”
“Oh, yessir,” said MacNeil quickly, “I know that. But I ain’t sick.” He didn’t feel that sick, anyway. “I’m Spaceman Second MacNeil, sir, from B Company. Could I ask you something, sir?”
Pilar sighed a little, then smiled. “Go ahead, spaceman.”
MacNeil wondered if maybe he’d ought to ask the doctor about his sacroiliac pains, then decided against it. This wasn’t the time for it. “Well, about the food. Uh ... Doc, can men eat monkey food all right?”
Pilar smiled. “Yes. What food there is left for the monkeys has already been sent to the men’s mess hall.” ”

“ The Space Service officers and the scientists discussed the problem for over an hour, but they came to no promising conclusion.
At last, Colonel Fennister said: “Very well, Dr. Pilar; we’ll have to leave the food supply problem in your hands. Meanwhile, I’ll try to keep order here in the camp.”
SM/2 Broderick MacNeil may not have had a top-level grade of intelligence, but by the end of the second week, his conscience was nagging him, and he was beginning to wonder who was goofing and why. ”

“ We’ll feed him more of the ... uh ... what’d he call ’em, Smathers?”
“Banana-pears.”
“We’ll feed him more banana-pears, and keep checking. If he is still in good shape, we’ll ask for volunteers.”
“Good enough,” said the colonel. “I’ll keep in touch.”
On the morning of the third day in isolation, MacNeil rose early, as usual, gulped down his normal assortment of vitamins, added a couple of aspirin tablets, and took a dose of Epsom salts for good measure. Then he yawned and leaned back to wait for breakfast. He was certainly getting enough fresh fruit, that was certain. ”

“ It is as old as Mankind, and a great deal stupider. It is the position of a beleaguered group which lacks one simple essential to keep them alive until help comes.
“A fighting outfit, suppose, has enough ammunition to stand off two more attacks ”